Universal PCB for Purifi 1ET400A amps

They can, but they need to have paets from bom. If there isn't any, then you can pick replacement or order parts to arrive there. Since parts aren't standard, you pay additional fee for each part on the board plus several other fees, on top of assembly fee. It's not worth it on small batches.
 
I re-looked at the Mono buffer. I think all components are solderable (no SMD or components that need special skill). It might be fun to pick up the solder iron. If I want to use 1612, any rough estimate of the cost before I go on to Mouser? I'm trying to stick to the Purifi Eval1 as much as possible.
 
This one?

image.jpg